An entire fabrication process, for example the fabrication of sheet metal, consists of many machines and is considered as having a job-shop environment, where jobs have their own process routings visiting these machines. However, the decision as to which jobs are to be processed on which individual machine is made via the company's production routings. Setups on machines incur when machines change from processing one job to another. Thus, the problem is defined here as a single machine-scheduling problem with setup. Moreover, jobs often have different levels of importance (priorities). The levels of importance are assigned by weight numbers, the higher the weights, the more important the jobs are. The company measures its performance by means of weighted number of late delivery. Currently, the Weighted Shortest Processing Time (WSPT) heuristic is used by conventional fabrication scheduling systems to address this fabrication problem. However, these conventional fabrication systems yield poor or inconsistent results